Fire prevention apparatus for motion picture projecting machines



3 Sheets-Shree?l 1 W. M. HALIBURTON ET AL FIRE PREVENTION APPARATUS FORMOTION PICTURE PROJECTING MACHINES Filed March l5, 1937 f Aug. 9, 1938.

INVENTGRS F1131 .awV-aw ATT OR N EY Aug 9, 1938. w. M, HALIBURTON ET AL2,126,108

FIRE PREVENTION APPARATUS FOR MOTION PICTURE PROJECTING MACHINES FiledMarch 15, 1937 5 Sheets-Sheet 2 N 0E www Y OBE m TD E www m1 mm mmvvflnM m .Iw g E, m 7 A..

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Aug. 9, 1938. w. M, HALIBURTON ET Al. 2,126,108

FIRE PREVENTION APPARATUS FOR MOTION PICTURE PROJECTING MACHINES FiledMarch l5, 1957 3 Sheets-Sheet 5 /isb 51 1s 563/- e6 es F105 as 30 18h 3634 B90/ INVENTORS 52 WMHALJBURTON 33 R-XVANDETTE es BY 8 '55 l FIG-4 E?@9 'ZTM Patented Aug. 9, 1938 PATENT OFFECE FIRE PREVENTION APPARATUSFOR MO- TION PICTURE PROJECTING MACHINES William M. Haliburton, MontrealWest, Quebec,

and Romeo X. Vandette, Dorval, Quebec, Canada Application March 15,1937, Serial No. 130,820

11 Claims.

This invention relates to motion picture projecting machines andparticularly to fire prevention apparatus of the type disclosed in ourcopending application Serial No. 89,826, filed July The fire preventionapparatus disclosed in said application comprises a plurality ofelectrically actuated control devices arranged to perform theirrespective functions automatically in response to breakage of the film,said devices comprising (l) a. switch which is operated to opencircuitthe film operating motor and thus interrupt feeding of the film past theexposure opening; (2) a dowser which is operated to a light interceptingposition between the light source and the film to prevent ignition ofthe film; (3) a cutter which is operated to sever the film at a pointclose to the film outlet of the upper film magazine and tosimultaneously clos-e said outlet so that, in the event of lm ignitionin the projector head., the fire will be prevented from spreading intothe upper film magazine; and (4) a locking device which is operated tolock the door of the upper lm magazine in closed position. In this priorapparatus the switch, film cutter, dowser and magazine lock areindependently mounted in rather scattered relation and separate coils orsolenoids are employed for controlling the operation of the cutter,dowser and magazine lock.

The purpose of the present invention is to provide a more compact,convenient and commercially desirable assembly in which the switch,cutter, dowser and magazine lock are mechanically interlinked andcontrolled by a single control coil or solenoid, thus dispensing withthe two control coils or solenoids previously employed for controllingthe dowser and magazine lock.

In the preferred embodiment of this invention,

49 the film cutter, dowser and magazine lock are Y associated with acommon base interposed between the upper film magazine and the projectorhead. This base also carries a control coil or solenoid which isoperated at the proper time to release a latch normally holding thecutter in a retracted or inoperative position. This solenoid iscontrolled by a momentary contact switch which, together with the mainmotor switch, may be mounted either on the upper film magazine or on thesame base which carries the cutter, dowser and magazine lock. The twoswitches, together with the dowser and magazine lock, are mechanicallyinterlinked with the cutter so as to be automatically operated therebywhen the cutter is released and operated to its film shearing andmagazine sealing position. The control coil or solenoid which governsthe operation of the cutter is energized to release the cutter at theproper time through the agency of a normally open control switcharranged to be automatically closed in response to breakage of the filmpassing through the projector head.

Proceeding now to a more detailed description of this inventionreference will be had to the accompanying drawings, in which- Fig. 1 isa partial rear elevation of the lm feeding mechanism of a motion.picture projecting machine. In this view the elements entering into thepresent invention are shown in full lines while the conventionalelements are shown in dotted outline.

Fig. 2 is a vside elevation looking toward the left hand side of theassembly appearing in Fig. l.

Fig. 3 is a detail view of the cutter assembly including the latch bywhich the cutting blade is normally held in a retracted or inoperativeposiion.

Fig. 4 is a View similar to Fig. 3 but showing the solenoid by which thecutter releasing latch is controlled.

Fig. 5 is a fragmentary perspective View, partly in section, showing themanner in which the cutter, dowser and magazine lock are mechanicallyinterlinked and associated with a. common basev interposed between theupper film magazine and the projector head.

Fig. 6 is a wiring diagram.

In these drawings the upper lm magazine and the projector head of aconventional motion picture projecting machine are respectivelyindicated at 5 and 6. The magazine contains the reel 1 from which thefilm 8 is fed past the exposure opening 9 by guide rolls It, II and I2and cooperating feed sprockets I3, I4 and I5. The lower film magazineand other conventional elements that would normally appear have not beenshown since such disclosure is not essential to an understanding of theinvention hereinafter described.

As best shown in Figs. l and 5, a hollow boxlike casting II and a knifeguide I8 are interposed between the magazine 5 and the projector head 6.The casting Il is shown as a rectangular structure open at the top andhaving the upper edges of its side and end walls curved to fit thecircular wall of the magazine 5. The bottom wall of the casting,designated Ila., is provided with a slot IIb for the passage of the film8. This slot registers with a similar slot I8a formed in the underlyingknife guide I8.

The upper surface of the knife guide I8 (compare Figs. 3 and 4) isrecessed to provide a guideway |8b in which the knife blade 2li isslidably arranged. The travel of the blade in either direction islimited by a stop pin 2l (Fig. 3) having its lower end xed to the knifeguide I8 and its upper end engaged in the knife slot 22 which iselongated in the longitudinal direction of the blade.

The knife blade 2D is shown held in a retracted position against theresistance of the blade actuating springs 23 which normally tend toproject the blade across the previously mentioned lm Slots I'lb and 18a.The blade .is held in this retracted position by a pivotally mountedcatch 24 engaged in the notch 25 shown in Fig. 3. The catch 24 ispivotally mounted on a suitable pivot 26 by means ci the sleeve portion21 which is provided with a vertically extending arm 28. The upper endof arm 28 is bifurcated to straddle the armature 29 of the knife releasesolenoid 30 and lies between inner and outer abutments 3| and 32 xed tosaid armature.

As shown more particularly in Fig. 4, the coil portion of solenoid 3D issupported between the arms 33 and 34 of a bracket 35 fastened to avertically disposed plate 3$ mounted at one end of casting Il', saidplate being provided with a suitable slot (not shown) for the passage ofthe knife blade 20. The armature 29 is normally biased to a latchapplying position by a spring 31 confined between the bracket arm 33 andthe enlarged end 29a of the armature. When the solenoid is energized thearmature 29 is moved axially against the resistance of the spring 3l toswing the catch 24 clear of the notch 25, thus releasing the knife blade20 and permitting it to be projected across the slots ill) and Ia by theknife actuating springs 23. When thus operated the knife blade 20 servesto sever the film and to simultaneously close off the iilm outlet of theupper magazine.

As shown in Fig. 6, the coil of solenoid 3U is connected in series witha normally open iilm actuated switch 4G and a normally closed momentarycontact switch 4l. Switch 4U (see Fig. 1) is carried by one end of alever 42 mounted to swing vertically about an intermediate pivot 43. Theremaining end of lever 42 is equipped with a film engaging roller 44.Under normal operating conditions the lm serves, through its engagementwith the roller 44, to hold the lever 42 and switch 4G in the positionshown in Fig. 1. When the Iilm breaks the lever 42 swings in acounter-clockwise direction so that the switch 4i) is tilted to acircuit closing position, thus energizing the coil of the solenoid 29 torelease the knife holding catch 24.

The switch 4l, together with the main motor switch 45, is carried by atiltably mounted support 45 located within a switch housing 4l iastenedto the lm magazine 5. The support 46 is mounted to swing about a pivotalaxis 43 and is provided with a depending arm 49. The lower end of arrn49 is slotted as at 50 to receive a lateral extension 5l provided at theouter end of the knife blade 20. The extension 5| is preferably formedas an integral or rigid continuation of one of the knife lugs 52 towhich the outer ends of the knife actuating springs 23 are connected,the inner ends ci said springs being suitably anchored to the previouslymentioned plate 36.

When the knife blade 20 is projected to its operative position by theaction of the springs 2i! the extension 5I acts, through the arm 49, totilt the support 45 to the left so that the normally closed switches 4land 45 are tilted to circuit opening positions. The opening of theswitch 4i disrupts the supply of current to the knife release solenoid39 while the opening of the switch 45 disrupts the supply of current totlie operating motor 53 (Fig. 6) which operates the conventional iilindrive gearing (not shown).

The dowser which is interposed between the light source and the film toprevent ignition of the latter in case of breakage is indicated at 55.This dowser is attached to one end of a lever 55 by which it is normallyheld in the retracted or elevated position shown in Fig. 1. The lever 55is mounted to swing about an intermediate pivot 5i carried by a pair oflugs 59 depending from the laterally projecting arm 59 of a suitablebracket til. The free end of lever 56 is held, by spring 6l, in contactwith a vertically slidable pin 62 working in a vertical opening formedin the bracket arm 53. rEhe upper end of pin B2 is engaged by a cam (i3fixed to one end of a shaft 64 which extends transversely through abearing opening in the bracket 6U. A crank arm `|56, fixed to theopposite end of shaft 64, is connected by link li'l to one end of a bar68 which is slidably attached to one side of the casting il by the pinand slot connections 69. The opposite end of bar 38 is fastened by link"H to the arm 49 of the tiltably mounted switch support 46.

Under normal operating conditions the cam 63 is positioned as shown inFigs. l and 5 and acts, through the pin 62 and lever 56, to hold thedowser 55 in its elevated position. When the cutter is projected to itsfilm shearing position by the springs 23 the resulting movement of theswitch tilting arin 49 acts, through link il, bar Bil, link il? and arm9G to swing the cam `53 in an anti-clockwise direction. rThe prole ofthe cam is Such that this swinging movement per-A mits the pin 52 tomove upwardly thus allowing lever 55 to swing in an anti-clockwisedirection until the dowser 55 is lowered to a position closing theexposure opening 13.

The bracket BG which is lxed to or formed integral with one end of thecasting I7 also carries a transversely extending shaft 74 mounted in asuitable bearing l5. One end of shaft 14 carries a latch arm 'i6 which,when the shaft is rotated in a counter-clockwise direction from theposition shown in Fig. l, is adapted to swing to a position overlyingthe outer side of the magazine cover to thus secure the cover in itsclosed position. An arm Ti', fixed to the opposite end of shalt i4, isconnected at its free end to the previously mentioned link 67. It willthus be seen that the catch 1G mechanically interlinked with the cutterblade 20 so as to be automatically operated thereby when the cutterblade is actuated by the springs 23.

Having thus described our invention, what we claim is:-

l. Fire prevention apparatus for motion picture projecting machinescomprising normally inoperative film cutting means adapted toautomatically sever the iilm close to the upper iilm magazine inresponse to breakage of the film within the projector head and normallyinoperative auxiliary control devices mechanically interlinked with saidcutting means so as to be automatically actuated thereby, said auxiliarydevices including a switch which is operated to open-circuit the linoperating motor and thus interrupt feeding of the Iilni past theexposure 7K5.,

opening, a dowser which is operated to a light interceptingposition/.between the light source and film to prevent ignition of thefilm and a locking device which is operated to lock the door of theupper .nlm magazine in closed position.

2. Fire prevention apparatus for motion picture projecting machinescomprising normally inoperative film cutting means adapted toautomatically sever the film close to the upper lm magazine in responseto breakage of the nlm within the projector head and normallyinoperative auxiliary control devices mechanically interlinked-with saidcutting means so as to be automatically operated thereby, said auxiliarydevices including a dowser which is operated to a light interceptingposition between the light source and iilm to prevent ignition of thefilm andl a locking device which is operated to lock the door-of theupper film magazine in closed position.

3. Fire prevention apparatus for motion picture projecting machinescomprising normally inoperative lm cutting means adapted toautomatically sever the film close to the upper iilm magazine inresponse to breakage of the film within the projector head and anormally inoperative locking device mechanically interlinked with saidcutting means so as to be automatically operated thereby to a positionlocking the door of the upper film magazine in closed position.

4. Fire prevention apparatus for motion picture projecting machinescomprising a motor control switch included in the circuit of the lmoperating motor, means functioning automatically in response to breakageof the film within the projector head to operate said switch to aposition disrupting the flow of current to said motor and a normallyinoperative locking device mechanically interlinked with said switch soas to be mechanically operated thereby to a position locking the door ofthe upper iilm magazine in closed position.

5. Fire prevention apparatus for motion picture projecting machinescomprising a motor control switch included in the circuit of the filmoperating motor, means functioning automatically in response to breakageof the lm within the projector head to operate said switch to a positiondisrupting the ow of current to said motor and normally inoperativeauxiliary control devices mechanically interlinked with said switch soas to be automatically operated thereby, said auxiliary devicesincluding a dowser which is operated to .a light intercepting positionbetween the light source and film to prevent ignition of the lm and alocking device which is operated to lock the door of the upper nlmmagazine in closed position.

6. Fire prevention apparatus for motion picture projecting machinescomprising a cutter for severing the iilm close to the upper filmmagazine, means normally biasing said cutter to a iilm cutting position,means releasably holding said cutter in a retracted position, meansfunctioning automatically in response to breakage of the lm in theprojector head to release said holding means and permit the cutter tomove to its film cutting position under the iniiuence of said biasingmeans, a motor control switch included in the circuit of the filmoperating motor, a tiltably mounted support carrying said switch, saidsupport being normally tilted to a switch closing position and meansmechanically interlinking said support with said cutter whereby thesupport is tilted to a switch opening position as the cutter moves toits iilm cutting position.

7. Fire prevention apparatus for motion picture projecting machinescomprising a cutter for severing the lm close to the upper iilmmagazine, means normally biasing said cutter to a lm cutting position,means releia-sably holding said cutter in a retracted position, meansfunctioning automatically in response to breakage of the lm in theprojector head to release said holding means and permit the cutter tomove to its iilm cutting position under the influence of said biasingmeans, a normally inoperative dowser adapted to be moved to an operativeposition between the light source and the lm to prevent ignition of thefilm, means including a cam for operating the dowser to and from itslight intercepting position and means mechanically interlinking said camwith said cutter whereby the dowser is operated to its lightintercepting position in response to movement of the cutter to its iilmsevering position.

8. Fire prevention apparatus for motioncpicture projecting machinescomprising a cutter for severing the film close to the upper iilmmagazine, means normally biasing said cutter to a film cutting position,means releasably holding said cutter in a retracted position, meansfunctioning automatically in response to breakage of the film in theprojector head to release said holding means and permit the Cutter tomove to its iilm cutting position under the iniiuence of said biasingmeans, a iilm magazine lock including a rotary shaft equipped with alocking member at one end adapted to be moved to and from a lockingposition over the cover of the upper film magazine and meansmechanically interlinking the opposite end of said shaft with saidcutter whereby said locking device is automatically operated to itslocking position as the cutter moves to its lm se'vering position.

9. Fire prevention apparatus for motion picture projecting machinescomprising a cutter adapted to sever the lm at .a point close to theupper film magazine, means for biasing the cutter to a film cuttingposition, a latch normally holding the cutter in a retracted positionagainst the resistance of said biasing means, a normally deenergizedsolenoid adapted, when energized, to release said latch and permit saidcutter to move to its iilm cutting position under the influence of saidbiasing means, a normally open film actuated switch and a normallyclosed momentary contact switch connected in series with said solenoidand with va suitable source of current, means for automatically closingthe film actuated switch in response to breakage of the iilm within theprojector head, a tiltably mounted support on which the momentarycontact switch is carried, said support being -normally tilted to aswitch closing position and means mechanically interlinking said switchsupport with said cutter whereby said support is automatically tilted toa switch opening position in response to movement of the cutter to itsfilm cutting position.

1G. Fire prevention apparatus as set forth in claim 9 including anormally closed motor control switch mounted on said switch support andconnected in series with the film driving motor, said motor controlswitch being movable with said support to a circuit opening positionsimultaneously with the aforesaid movement of the cutter to its lmcutting position.

11. Fire prevention apparatus for motion picture projecting machinescomprising a cutter adapted to sever the film close to the upper nlmmagazine, means biasing said cutter to a nlm cutting position, areleasable latch normally holding the cutter in a retracted positionagainst the resistance oi' said biasing means, a normally deenergizedsolenoid connected to said latch and adapted, when energized, towithdraw the latch to a cutter releasing position to thereby permit thecutter to move to its nlm cutting position under the inuence oi saidbiasing means, a normally open film actuated switch connected in serieswith said solenoid and with a source of current, means for automaticallyclosing said switch in response to breakage of the film within theprojector head, a normally closed momentary contact switch connected inseries with said solenoid and said film actuated switch, a normallyclosed motor control switch connected in series with the film operatingmotor, a tiltably mounted support carrying said momentary contact switchand said motor control switch, said support being normally tilted to aswitch closing position, and an arm xed to said support and secured tosaid cutter whereby said support is automatically tilted to a switchopening position as the cutter moves to its film severing position, thearrangement being such that the resulting opening of the momentarycontact switch serves to deenergize the solenoid while the resultingopening oi' the motor control switch serves to interrupt the supply ofcurrent to the lm driving motor.

WILLIAM M. HALIBURTON. ROMEO X. VANDETIE.

